That's another worry,you think they are slabbed correctly,turns out the slab is faked so the content is also worthless,or worst scenario,the slab is correct,and it's a third party grader that's wrongly slabbed a fake.I think with the internet,more and more people will start to rely on a slabbed coin for authenticity. If you can prove that they have slabbed a fake, the more respectable TPGs like PCGS, NGC or CGS will compensate you to the market value of the real coin. For NGC or CGS, you can use the number on the slab on their databases and get a photo of the coin originally slabbed. This should tell you if you have got a fake coin in a fake slab. NGC only takes pictures of the coins that have paid the extra fee for pictures. Almost half or more don't have pictures. I think CGS takes pic's of all coins. (I think). They have had pic's of all of the coins I have followed up on at least! If you are referring to CGS UK, I believe that they do now always take pictures, but have not always done so. There used to be a cheaper option that gave you a slab and a grade, but no photo.